On April 11, the Natural Resources Defense Council said environmental groups will consider filing a suit with the federal District Court should the Environmental Protection Agency (EPA) miss the April 13 deadline to release its final rule on new fossil fuel-fired power plant carbon dioxide performance standards. The same day, the EPA reported that work is being done on the final rule although a timeline has not been finalized. According to statute, the EPA must finalize the rule within one year of proposal; the EPA has yet to send the final rule to the Office of Management and Budget which is seen as the last step before being published. The proposed performance standard is 1,000 pounds of carbon dioxide per megawatt-hour, and all sources are required to comply regardless of fuel type.